The present invention relates to a cleaning device for an intermediate transfer body for use in an image forming apparatus for forming images with use of the intermediate transfer body.
Known as one of the conventional electrophotographic image forming apparatuses is an image forming apparatus in which a developer image formed on a photoreceptor is primarily transferred onto an intermediate transfer body and then the developer image is secondarily transferred from the intermediate transfer body to a paper sheet. Such an image forming apparatus normally has a cleaning device for removing undesired substances such as residual developers on the intermediate transfer body after the secondary transfer as well as paper powders and dust attached onto the surface of the intermediate transfer body.
The cleaning device is typified by those removing the residual developer and the like by bringing a metal or rubber blade into pressure contact with the surface of the intermediate transfer body. In order to cope with the case where such a blade cannot provide a sufficient cleaning effect or the case where it is necessary to remove a so-called separation streak, which are a streak formed by a residual developer having been already collected by the blade when the blade is separated from the intermediate transfer body, a technology for placing a seal member serving as another cleaning member on the surface of the intermediate transfer body on the downstream side of the blade with respect to the moving direction has been proposed.
However, the conventional technology for placing the seal member on the downstream side of the blade has such a problem that the seal member suffers creep deformation with the elapse of time and this hinders fulfillment of a sufficient cleaning effect.
Moreover, a cleaning device having a seal member placed on the upstream side of a blade, which has been disclosed in U.S. Pat. No. 5,991,568, is not capable of cleaning the separation streak remaining when the blade is separated from the intermediate transfer body.